Years of training

Along with manufacturing, LG also does some R&D in Vietnam for auto infotainment and software. But it takes a long time to train employees to perform tasks more complex than assembly. On average, LG has to train R&D-centric employees for three years before they can work on their own projects.

About 30 percent of the white-collar staff members overseeing factory line workers and handling tasks like quality and assurance testing can work independently after four months. The rest need close supervision for a year. About 90 percent of line workers, the people actually putting together TVs and phones, work alone after a month.

See you at the checkout counter

Jabil builds most of its customers' point-of-sale terminals in its Vietnam factory. It saw a big jump in demand last year as companies got ready for new standards rolling out in late 2015. All sales terminals will have to work with NFC (near field communication) chips, which are what enable contactless mobile payments.

Vroom vroom

Most of Jabil's 2,600 employees commute to its factory by motorbike -- the most common mode of transport for the Vietnamese. There were about 39 million motorbikes registered in all of Vietnam as of early 2014. Ho Chi Minh City is currently building its first subway line.

Building boom

Over the past six years, Samsung has earmarked about $9 billion to construct factories in Vietnam. That includes a new consumer electronics facility in the Saigon Hi-Tech Park, just down the road from Jabil and Intel.

Jobs jobs jobs

Samsung is one of the biggest tech companies in not only the world but also in Vietnam. It has 110,000 employees in the country, surpassing the number of worker in Korea and China. Most of the employees assemble mobile devices, with Samsung making about 30 percent of its smartphones in Vietnam last year.

Tallest building in Saigon

Along with operating several factories in Vietnam, Samsung also houses sales and marketing operations in the Bitexco Financial Tower in downtown Ho Chi Minh City. The building, the tallest skyscraper in the city, includes a helipad, the Saigon Skydeck lookout on the 49th floor, a bar on the 52nd floor, a cinema and other retail stores and dining options.